LONG-TERM DEBT (2.5% Convertible Senior Notes Due 2023) (Details) |
12 Months Ended | |
|---|---|---|
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Dec. 31, 2018
USD ($)
$ / shares
shares
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Mar. 31, 2018
USD ($)
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| 2.5% Convertible Senior Notes Due 2023 [Member] | ||
| Debt Instrument [Line Items] | ||
| Face amount | $ 550,000,000 | $ 550,000,000 |
| Interest rate, stated percentage | 2.50% | 2.50% |
| Conversion ratio | 0.0147005 | |
| Conversion premium | 54.40% | |
| Last reported sale price used to calculate conversion premium | $ / shares | $ 44.05 | |
| Maximum number of shares issuable upon conversion | shares | 8,100,000.0 | |
| Carrying amount of equity component | $ 64,000,000 | |
| Unamortized debt discount balance | $ 55,000,000.0 | |
| Debt discount amortization period | 4 years | |
| Effective interest rate | 5.70% | |
| 2.5% Convertible Senior Notes Due 2023 [Member] | Redemption, Defined Changes of Control [Member] | ||
| Debt Instrument [Line Items] | ||
| Redemption price, percentage | 100.00% | |
| 2.5% Convertible Senior Notes Due 2019 and 2023 [Member] | ||
| Debt Instrument [Line Items] | ||
| Interest rate, stated percentage | 2.50% |
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- Definition The percentage amount by which the convertible debt's if-converted value exceeds its principal amount at the balance sheet date, regardless of whether the instrument is currently convertible. No definition available.
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- Definition The last reported sale price of common stock, used to calculate the conversion premium on the convertible debt. No definition available.
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- Definition The maximum number of shares that could be issued to satisfy the conversion, assuming the notes are fully settled in shares. No definition available.
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- Definition The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after accumulated amortization, of debt discount. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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